Check the listing for details. 15PK Sling Psychrometer Classroom Kit - Eisco Labs. Condition: New. Listed at 35.99 USD. 15PK Sling Psychrometer Classroom Kit - Eisco Labs CLASS SIZE KIT || Pack of 15 Sling Psychrometer Kits to outfit an entire class. Each 7-piece Kit contains: (1) dry bulb thermometer (6.5"L), (1) wet bulb thermometer (6.5"L), (1) wooden handle (5"), (1) cloth sleeve, (1) screw, (2) rubber bands, (1) instruction guideEASY ASSEMBLY || The apparatus is easily assembled by attaching the two thermometers to the end of the handle and placing the moistened cloth sleeve over the wet bulbEASY OPERATION || Once assembled the user swings the apparatus for 30 seconds then records the temperatures on both the wet-bulb and dry-bulbPSYCHROMETRIC CHARTS || Relative humidity and dew point are determined by comparing the temperature difference between wet and dry bulb readings against the included psychrometric chartsGREAT FOR STUDYING WEATHER || The interactive, hands-on Sling Psychrometer promotes student understanding of meteorology and weather Classroom pack of 15 Sling Psychrometer Kits are easily assembled by attaching the two thermometers to the end of the handle and placing the moisture cloth over the wet bulb. Once assembled the user can swing the apparatus and then read the difference in temperature between the wet-bulb and dry-bulb to determine the relative humidity and dew points using the included psychrometric charts found in the instruction guide. Contents: (1) dry bulb thermometer (6.5"L) (1) wet bulb thermometer (6.5"L) (1) wooden handle (5") (1) cloth sleeve (1) screw (2) rubber bands (1) instruction guide Product Details Brand Eisco Product Type MPN PH1120142PK15 Check out my other items.